That last verse (or two) must be one of those floating verses.
Similar ending in Froggies Courting

That was the end of 1,2,3 (x3)
Mouse and the ?rat? and the little froggie

There's bread and cheese upon the shelf (x3)
If you want any more you can sing it yourself

Do they share a tune, too? One of the froggie versions has a non-verbal line ending ('ah, hmm' - or however you spell it)